Gas gun



J. H. WILY July 17, 1956 GAS GUN Filed Feb. 26, 1953 INVENTOR. JAMES H.wlLY ATTORNEYS GAS GUN James H. Wily, Bethlehem, Pa. ApplicationFebruary 26, 1953, Serial No. 339,151 3 Claims. (Cl. 42-55) Thisinvention relates to a gas gun of the type constructed to contain waterand provided with a charger whereby calcium carbide is loaded in thewater in the gun, the gun having an igniter for the acetylene gasgenerated within the gun itself. The gun must contain air to support thecombustion of the gas and customarily the calcium carbide isproportioned so that the gun fills with a gas and air mixture whichignites and burns inside of the gun itself.

The main purpose of such a gun is to produce a loud concussionaccompanied by a spectacular muzzle blast. Usually the device is made inthe form of a small cannon which is useful in connection with thestarting of sporting races, as a toy, for general celebration purposesand the like.

One of the objects of the present invention is to provide this kind ofgun in a form providing for a louder report and a more impressive muzzleblast, and which obtains these effects more reliably and consistently.Another object is to provide such a gun with a repeating loading deviceproviding accurately proportioned charges of calcium carbide. A furtherobject is to generally simplify the operation of this type of gun so asto obtain loud reports and spectacular muzzle blasts without requiringthe skill necessary when operating prior art guns of this type.

A specific example of a gas cannon made in accordance with the presentinvention is illustrated by the accompanying drawings in which:

Fig. 1 is a side view of the cannon;

Fig. 2 is a top view;

Fig. 3 is a vertical section taken on the line 33 in Fig. 2;

Fig. 4 is a horizontal cross section taken on the line 4-4 in Fig. 3;and

Fig. 5 is a vertical cross section taken on the line 5-5 in Fig. 3.

The illustrated cannon is intended primarily for use as a toy but as canbe seen from Figs. 1 and 2 it has a realistic appearance. Its carriageis formed by wheels 1 and a tailpiece 2, and the gun itself comprises agenerally cylindrical breech portion 3 and relatively long barrel 4. Theinvention is embodied by the breech portion 3 as described below.

This breech portion 3 forms a gas generating chamber 5 having aliquid-containing lower portion or sump 6. This sump is in the form of arectangular box depending from the generally cylindrical contour of thebreech portion 3 and which is adapted to be partly filled with water.This gas generating chamber has an outlet 7 in its front wall and whichconnects directly with the barrel 4, and it has a port 8 formed in itsback wall 9. A preignition chamber 10 connects with the gas generatingchamber 5 through the port 8, and this chamber 10 has an inlet 11provided with a closure 12 in which is mounted a piece of pyrophoricmetal 13.. This piece of pyrophoric metal is mounted so that it bearsagainst a sliding striker plunger 14 which when sharply depressed by annited. States Patent 0 external operator ice 15 showers igniting sparksinto the 1 chamber 10. The closure 12 applies to the top of the into thewater close to this outlet.

chamber 10 by means of a bayonet joint so that the closure may be easilyremoved and replaced, the inlet 11 functioning to admit air to thechamber 10 when the closure is removed.

A threaded hole 16 is formed in the top of the gas generating chamber 5so as to receive the correspondingly threaded bottom 17 of a hopper 18.This hopper has a downwardly and forwardly slanting bore 19 formedthrough its bottom and in which a plunger 20 is reciprocatively fitted.The lower side of this plunger 20 is formed with a recess 21 having theshape of an annular groove so excessively eccentric to the plunger 20 asto be free from the latters upper side. The plunger is reciprocative inthe bore between an up position, shown by Fig. 3, where the recess 21 isinside of the hopper 18, and a down position where the recess 21 is opento the inside of the gas generating chamber 5. The plunger is biased toits up position by a hairpin spring having one leg 22 insertedrelatively closely in a hole 23 formed in the bottom of the hopper, andits other leg 24 inserted in a hole 25 formed partly through the upperside of the plunger 20. The bore 19 and plunger 29 are cylindrical sothat the latter may turn rotatively to difierent positions. This turningaction is permitted because the hole 25 is relatively larger in diameterthan is the springs leg 24, but at the same time the diameter of thehole 25 is proportioned so that the springs leg 24 limits the plungerrotation to a range of rotative positions wherein the recess 21 alwaysfaces or is open in a generally downward direction. The hairpin springis laterally braced by the opposite sides of the hopper 18 but thespring may swing in moving from one side to the other, so the hole 25should be proportioned with this loose action in mind. It is necessaryto prevent the recess 21 from ever occupying an up position so thatmaterial will not fall freely from this recess.

In operation water is loaded in the sump 6 so that the latter is abouthalf full, and powdered calcium carbide is placed in the hopper 18, thelatter having a lifting swing cover 26. The upper end of the plunger 20projects 21 is proportioned so as to assure filling the gun with arelatively rich mixture of acetylene gas and air with the excess of theacetylene possibly being even so great as to prevent ignition.

Due to the fact that the plunger slants downwardly toward the outlet 7the calcium carbide charge is loaded The generated gas crowds backwardlyand forwardly in the chamber 5, the relatively small size of the outlet7, as compared to the chamber, choking hack free flow in a forwarddirection, and the even smaller port 8 choking back flow into thepreignition chamber 10. If the gun has been fired shortly before, priorto the loading operation the closure 12 is removed and air is blown intothe chamber 10 to make certain that it is loaded with air. There is arelatively wide range of mixtures of acetylene gas to air ratiospermitting combustion, so pushing down on the actuator 15, causingoperation of the igniter, ignites the mixture in the chamber 10 withreasonable certainty.

Since there is no way to control practically the gas to air ratio therate of combustion in the pre-ignition chamber is more or lessunpredictable as it is in the case of the entire gun designed in theprior art manner. However, in the illustrated gun the pre-ignitionchamber functions to develop a rush or flow of moving mixture due to theexpansion involved, thus forcing its way through the port 8 and drivingout the rich mixture in the chamber the pre-ignition chamber morereadily. main port portion and the outlet 7 are of circular contour soas to promote the driving of the rich gas through the outlet 7 and thebarrel 4 to the atmosphere. This is to assure hat regardless of theviolence of the explosion in the pro-ignition chamber 10, there willpositively be a good muzzle blast which will provide the main report.

Due to the ability of the plunger to move to diflierent rotativepositions there is little chance for wear to form longitudinal groovesin the plunger so as to cause it to leak when in its normal upwardposition. Because the recess 21 must always face downwardly each load isfully dumped for each operation of the plunger and each load has theexact volume determined by the volume of the recess 21.

Another advantage of the new gun is that when the closure 12 is removedit is not necessary to completely clear the gun of the products ofcombustion of a previous firing. If the chamber 10 is blown full of airthe preignition eflPect may be obtained with certainty, the dischargedrich gas and air mixture then exploding in the atmosphere, beyond themuzzle of the gun barrel.

The dropping of the calcium carbide charge in the front of the sump 6has the advantage that the gas is generated near the outlet 7 and moreremote from the port 8, so that a rich mixture builds up in the gun bythe time there is enough gas in the chamber 10 to ignite when theigniter is operated.

The breech portion 3 and sump 6 may be made from cast metal with thefront of the sump 6 providing a bathing action for choking back the flowthrough the outlet 7 during the gas generating phase. The port 8 withits ex- I claim:

1. A gas gun including a gas-generating chamber having .aliquid-containing lower portion and having an outlet and a portlocatedabove said portion, means for loading said lower portion with a chargereacting with liquid therein to generate combustible gas, a pro-ignitionchamber connected with the gas-generating chamber through said port andhaving an air inlet provided with a closure, and an igniter for thepro-ignition chamber, whereby preignition of the portion of thegenerated gas entering the Where the recess is inside of thegas-generating chamber, and a spring biasing said plunger to its upposition, said plunger being free to tum throughout a range of rotativepositions in saidbore wherein the'plungers recess is generallydownwardly facing.

2. A gas gun including a gas-generating chamber having aliquid-containing lower portion and having an outlet and a port locatedabove said portion, means for loading said lower portion with a chargereacting with liquid therein to generate combustible gas, a pre-iguitionchamwhere the recess is. inside of the gas-generating chamber, and aspring biasing said plunger to its up position, said positions in saidbore wherein the plungers recess is generally downwardly facing, saidspring comprising a hair- 3. A gas gun including a gas-generatingchamber having. a liquid-containing lower portion and having an outletand a port located above said portion, means for loading said lowerportion with a charge reacting with liquid therein to generatecombustible gas, a pre-ignition chamber connected with thegas-generating chamber through said port and having an air inletprovided with a closure, and an igniter for the pre-ignition chamber,whereby pre-ignition of the portion of the generated gas entering thepreignition chamber through said port, with air introduced through saidinlet, drives a burning volume mosphere therebeyond, the gas-generatingchamber having an opening in its top and said loading means cornprisinga hopper positioned over said opening and having a declining boreproviding communication between the inside of the hopper and thegas-generating chamber, a Plunger reciprocative in said bore and havinga recess in its side, the plunger being reciprocative between an upposition Where its recess is inside of the hopper and a down positionwhere the recess is inside of the gasgeneratiug chamber, and a springbiasing said plunger to its up position, said plunger being free to turnthroughout a range of rotative positions in said bore wherein theplungers recess is generally downwardly facing, said outlet and portbeing oppositely spaced in mutually opposed walls of the gas-generatingchamber, and said bore and plunger declining towards Said outlet so asto load charges of the material into the liquid adjacent to said outlet.

R f rences Cited in he tile ct thi p ten UNITED STATES PATENTS 1,624,086Wily Apr. 12, 1927 1,757,523 Grimm May 6, 1930 1,863,062 MacDonald June14, .1932 2,000,607 Peake May 7, 1935 was A A

